How to deal with a patient who's defiant, doesn't want to be clean and says he falls on purpose?

NEEDS a psychiatric evaluation. Who is calling 911? who has poa? do they know about this.? Who is his legal next of kin? If you are working for a company do an incident report and get your management involved.

Not knowing any history, it sounds as though "he", whoever he is, is attempting to cover for the fact that he's in failing health, mental and physical. Are you a relative? Aide? Tell us more. Does he have dementia?

You have the EMT's take him to the ER for xrays to be sure there are no fractures. Otherwise this is a game to him. They really hate going to the ER, they think they are going away for good.